Torben C. Rick

Paleocoastal marine fishing on the Pacific coast of the Americas: Perspectives from Daisy Cave, California

Analysis of over 27,000 fish bones from strata at Daisy Cave dated between about 11,500 and 8500 cal B.P. suggests that early Channel Islanders fished relatively intensively in a variety of habitats using a number of distinct technologies, including boats and the earliest evidence for hook-and-line fishing on the Pacific Coast of the Americas. The abundance of fish remains and fishing-related artifacts supports dietary reconstructions that suggest fish provided more than 50 percent of the edible meat represented in faunal samples from the early Holocene site strata. The abundance and economic importance of fish at Daisy Cave, unprecedented among early sites along the Pacific Coast of North America, suggest that early maritime capabilities on the Channel Islands were both more advanced and more variable than previously believed. When combined with a survey of fish remains from several other early Pacific Coast sites, these data suggest that early New World peoples effectively used watercraft, captured a diverse array of fish, and exploited a variety of marine habitats and resources.

Adaptive divergence despite strong genetic drift: genomic analysis of the evolutionary mechanisms causing genetic differentiation in the island fox (Urocyon littoralis)

The evolutionary mechanisms generating the tremendous biodiversity of islands have long fascinated evolutionary biologists. Genetic drift and divergent selection are predicted to be strong on islands and both could drive population divergence and speciation. Alternatively, strong genetic drift may preclude adaptation. We conducted a genomic analysis to test the roles of genetic drift and divergent selection in causing genetic differentiation among populations of the island fox (Urocyon littoralis). This species consists of six subspecies, each of which occupies a different California Channel Island. Analysis of 5293 SNP loci generated using Restriction‐site Associated DNA (RAD) sequencing found support for genetic drift as the dominant evolutionary mechanism driving population divergence among island fox populations. In particular, populations had exceptionally low genetic variation, small Ne (range = 2.1–89.7; median = 19.4), and significant genetic signatures of bottlenecks. Moreover, islands with the lowest genetic variation (and, by inference, the strongest historical genetic drift) were most genetically differentiated from mainland grey foxes, and vice versa, indicating genetic drift drives genome‐wide divergence. Nonetheless, outlier tests identified 3.6–6.6% of loci as high FST outliers, suggesting that despite strong genetic drift, divergent selection contributes to population divergence. Patterns of similarity among populations based on high FST outliers mirrored patterns based on morphology, providing additional evidence that outliers reflect adaptive divergence. Extremely low genetic variation and small Ne in some island fox populations, particularly on San Nicolas Island, suggest that they may be vulnerable to fixation of deleterious alleles, decreased fitness and reduced adaptive potential.

Archaeological survey, paleogeography, and the search for Late Pleistocene Paleocoastal peoples of Santa Rosa Island, California

Abstract The northern Pacific Coast is an important area for understanding human colonization of the Americas, but Late Pleistocene coastal sites are rare and interglacial sea level rise has inundated the continental shelf and the primary areas where Paleocoastal archaeological sites are likely to occur. Here we outline a terrestrial archaeological survey project designed to identify Paleocoastal sites on Santa Rosa Island, California. Using reconstructions of ancient shorelines and paleogeography, we predicted that sites might be found where lithic resources, freshwater springs, caves or rockshelters, and strategic vistas drew Paleocoastal peoples into the island interior. We identified nine new Paleocoastal sites, including four radiocarbon dated to >11,000 cal b.p. that are among the oldest sites on North America’s Pacific coast. Our targeted survey demonstrates an important technique for investigating island and coastal settings where sea level rise remains a significant challenge for locating early sites.

Our disappearing past: a GIS analysis of the vulnerability of coastal archaeological resources in California’s Santa Barbara Channel region

Coastal archaeological resources around the world often coincide with dense contemporary human populations and a rapidly changing physical environment. Projected sea level rise and urban expansion during the 21st century threaten to destroy much of our global coastal archaeological heritage. In this study, we adapt an environmental vulnerability analysis to quantify the threats of modern development and sea level rise on archaeological sites in California’s Santa Barbara Channel region. Using spatial and statistical techniques, we create a Cultural Resource Vulnerability Index that combines environmental factors, current and projected urban footprints, and archaeological site positioning. We illustrate the importance of this method for targeting threatened archaeological sites for mitigation and salvage research. In the process, we highlight the significance of coastal archaeological sites for helping better understand contemporary environmental and cultural issues, underscoring the need to preserve or salvage these sites for their significant research value.

Early New World maritime technologies: sea grass cordage, shell beads, and a bone tool from Cave of the Chimneys, San Miguel Island, California, USA

Recent excavations at Cave of the Chimneys (CA-SMI-603), located on San Miguel Island, revealed well-preserved sea grass knots, twined cordage, Olivella spire-ground beads, and a bone gorge. The assemblage, dated to roughly 8000 years ago, is dominated by S-twist cordage and includes an assortment of strands, loops, and knotted pieces. Wrapped sea grass knotted balls, including some stained red, suggest they may have had a decorative function. Unique among Paleocoastal assemblages of the area, these artifacts offer a rare glimpse into the non-lithic technologies of early Native Americans on the Pacific Coast of North America.

Recent Progress, Trends, and Developments in Island and Coastal Archaeology

ABSTRACT In the first issue of the Journal of Island & Coastal Archaeology published 10 years ago, Erlandson and Fitzpatrick (2006) outlined eight topics which demonstrated why island and coastal archaeology were relevant to understanding a host of issues related to human cultural and biological evolution across time and space. Here, we evaluate recent trends and developments in island and coastal archaeology and discuss how research over the last decade has changed and continued to illuminate the antiquity of maritime adaptations, human dispersals, historical ecology, and many other issues on a global scale. With rising seas and marine erosion threatening island and coastal archaeological sites around the world, archaeologists face urgent challenges in the coming decades as we continue to promote research and conservation of the global island and coastal archaeological record.

Where were the northern elephant seals? Holocene archaeology and biogeography of Mirounga angustirostris

Driven to the brink of extinction during the nineteenth century commercial fur and oil trade, northern elephant seal (NES, Mirounga angustirostris) populations now exceed 100 000 animals in the northeast Pacific from Alaska to Baja California. Because little is known about the biogeography and ecology of NES prior to the mid-nineteenth century, we synthesize and analyze the occurrence of NES remains in North American archaeological sites. Comparing these archaeological data with modern biogeographical, genetic, and behavioral data, we provide a trans-Holocene perspective on NES distribution and abundance. Compared with other pinnipeds, NES bones are relatively rare throughout the Holocene, even in California where they currently breed in large numbers. Low numbers of NES north of California match contemporary NES distribution, but extremely low occurrences in California suggest their abundance in this area was very different during the Holocene than today. We propose four hypotheses to explain this discrepancy, concluding that ancient human settlement and other activities may have displaced NES from many of their preferred modern habitats during much of the Holocene.

Ancient experiments: forest biodiversity and soil nutrients enhanced by Native American middens

The legacy of ancient human practices can affect the diversity and structure of modern ecosystems. Here, we examined how prehistoric refuse dumps (“middens”) impacted soil chemistry and plant community composition in forests along the Chesapeake Bay by collecting vegetational and soil nutrient data. The centuries- to millennia-old shell middens had elevated soil nutrients compared to adjacent sites, greater vegetative cover, especially of herb and grass species, and higher species richness. Not only are middens important archaeological resources, they also offer a remarkable opportunity to test ecological hypotheses about nutrient addition over very long time scales. We found no evidence, for example, that elevated nutrients enhanced invasion by non-native species as predicted by the fluctuating resource hypothesis. However, we did find that elevated nutrients shifted community structure from woody species to herbaceous species, as predicted by the structural carbon-nutrient hypothesis. These results highlight the long-lasting effects that humans can have on abiotic and biotic properties of the natural environment, and suggest the potential for modern patterns of species’ distributions and abundances to reflect ancient human activities.

SHELLFISH AND THE CHUMASH: MARINE INVERTEBRATES AND COMPLEX HUNTER-GATHERERS ON LATE HOLOCENE SAN MIGUEL ISLAND, CALIFORNIA*

Marine resources played an important role in fostering high population densities and cultural complexity among North American hunter-gatherers. In California, several researchers have emphasized the relationship among increases in fishing, marine mammal hunting, the development of more efficient watercraft, and increased sociopolitical complexity. Largely absent from discussions of emergent complexity is the changing role of shellfish in human subsistence economies. Analyzing marine shell from 12 Late Holocene sites on San Miguel Island, we illustrate the importance of shellfish in island subsistence economies and the evolution of Chumash complexity. The dietary importance of shellfish protein declined through time, but the density of shellfish remains increased dramatically in Late Holocene archaeological sites, suggesting that shellfish provided an important supplement to the higher yields of finfish and helped fuel growing human populations and sociopolitical complexity.

Comparing Faunal Remains and Subsistence Technology at CA-SMI-507: A 9,000-Year-Old Paleocoastal Shell Midden on San Miguel Island, California

ABSTRACT Data from many early California shell middens suggest that shellfish and plant foods were economic staples that provided early coastal people with a balanced diet rich in calories and complete proteins. Along the mainland coast, fish, land mammals, sea mammals, and birds were all exploited by early foragers, but the dominance of shellfish and plant foods is supported by both faunal and artifact assemblages. Faunal remains from most early Channel Island sites confirm this pattern, but most reconstructions have been based on small samples in which artifacts and vertebrate remains are often poorly represented. We examine human subsistence at CA-SMI-507, a ∼9,000-year-old shell midden where our test excavations and intensive surface collections recovered samples of artifacts and faunal debris. The faunal remains are dominated by shellfish remains, but numerous bifaces from the site suggest a substantial investment in hunting activities not represented in midden samples. When studying early island sites, archaeologists need to excavate larger samples to effectively evaluate faunal and artifactual evidence for the importance of marine fishing and sea mammal hunting.